Stereotaxic biopsy and radioactive implantation for interstitial therapy of tumors of the pineal region.

Stereotaxic biopsy was performed in 10 patients with tumors of the pineal region. On the basis of intraoperative tissue diagnosis, low-energy radioactive sources (125I) were implanted in seven patients for interstitial irradiation during the same stereotaxic procedure. Results were good in five cases. This therapeutic modality appears to be indicated in cases of proven low-grade malignancy, inasmuch as the implantation of radioactive sources in a highly malignant lesion carries the risk of severe, often irreversible, damage to the surrounding brain, because of possible seed migration.